The present invention relates to bicycles, and more particularly, to an aerobar assembly that includes an aerobar and an adaptor for mounting an actuating assembly to the aerobar.
An aerobar is an elongated bar that is typically attached to a bicycle handlebar, or alternatively, formed as a part of the handlebar itself. Although handlebars typically extend in a direction generally perpendicular to the path of travel, an aerobar is designed to extend generally along the direction of travel. When formed to be discrete from the handlebar, aerobars are formed in pairs.
When positioned on the bicycle, the cyclist will use the aerobars to help support her weight while assuming a more aerodynamic profile. The cyclist will typically bend over in an aerodynamic tuck position wherein the proximal portions of the cyclist's forearms (near her elbows), rest on pads attached to the handlebars with her hands and forearms extending forward of her chest, the cyclist's hands gripping the aerobar near its distal end to better pierce the air. The proximal end of the aerobar is positioned closest (rearward-most) to the bicycle frame while the distal end is farthest away (forward-most).
A prior art handlebar assembly 2 that includes a pair of aerobars 10, 13 is shown in FIG. 1A. The handlebar assembly 2 includes a transversely-extending handlebar 4 that is affixed at its center point onto a handlebar stem at the front of a bicycle. The handlebar 4 includes a laterally-extending portion 5 that extends generally perpendicular to the direction of travel of the bicycle. The end of the laterally-extending portion 5 of the handlebar terminates in handgrip portions 6. On a road bike, the handgrip portion 6 typically has a shape similar to a ram's horn. A pair of first and second forearm rests 7, 8 is attached to the laterally-extending portion 5 of the handlebar 4 and provides a surface upon which the cyclist can rest her forearms. Typically, the cyclist rests the portion of her forearms adjacent her elbows on the rests 7, 8. First and second aerobars 10, 13 are removably attached to the laterally-extending portion 5 of the handlebar 4, through first and second clip members 9, 11, respectively.
The prior art aerobar 10 shown in FIG. 1B is similar to the aerobar 10, 13 of FIG. 1A, both having a “chicane” type shape, best described as a stretched “S-shape” that generally includes a proximal straight portion, laterally and axially spaced from a distal straight portion by an angled medial portion connecting the proximal and distal portions, the transitions therebetween typically formed by smoothly transitioning curves. It is understood that the proximal, distal, and medial portions may take on any number of shapes, as may the transitions therebetween, in order to position the cyclist's hands in the desired aerodynamic tuck position.
Aerobar 10 is tubular and includes a proximal end 15 and a distal end 22. A generally straight or straight proximal portion 12 is disposed adjacent the proximal end 15. The proximal portion 12 transitions along a first curve 14 into a medial straight portion 16 that is angled or upturned relative to proximal portion 12. The upturned medial portion 16 then transitions along a second curve 18 into a straight distal portion 19, wherein the axis of the distal portion 19 is generally parallel to the axis of the proximal portion 12. The aerobar 10 may be made from a carbon fiber composite resin, or from a metal such as titanium, aluminum or steel.
In FIG. 1C, a prior art “ski tip” aerobar 98 is shown. This ski-tip aerobar 98 includes a proximal end 72 and a distal end 74. A relatively-longer (than aerobar of FIG. 1B) and straight proximal portion 76 transitions along a curve 78 into an upturned straight distal portion 80 to position the cyclists hand at a different location relative to the aerobar of FIG. 1B.
Looking to FIG. 1B, a shifter 40 is mounted to the aerobar 10. The shifter 40 includes a body 42 that is received by the distal end 22 of the aerobar 10. A shift lever 44 is pivotably coupled to the body 42. The body 42 includes an exteriorly-disposed portion 47 and an interiorly-disposed portion 46. The interiorly-disposed portion 46 is generally cylindrical in shape and is received within the hollow interior of the distal end 22 of the aerobar 10. The interiorly-disposed portion 46 may include one or more shims 48. An adjustment bolt (not shown) extends through the interiorly-disposed portion 46. By rotating the adjustment bolt, the diameter of the interiorly-disposed portion 46 is expanded radially outwardly thereby displacing the shims 48 to grip the internal walls 50 of the distal portion 19 of the aerobar 10.
The exteriorly-disposed portion 47 of the body 42 of the shifter 40 includes an end member 56 and a shift lever receiving member 58. The exteriorly-disposed portion 47 generally has a diameter that is greater than the diameter of the aerobar 10 and is configured to cover the open distal end 22 of the aerobar 10. The shift lever receiving member 58 is configured to receive the head 60 of the shift lever 44, such that a bolt 61 or other fastener can pass through an aperture 62 of the shift lever 44 and also pass through the aperture 64 of the body 42 to permit the shift lever 44 to pivotably engage to the body 42.
Another function of the body 42 is to provide an anchor for the distal end of the control cable 72 that extends between the shift lever 44 and the shift mechanism of the bicycle. The control cable 72 is actuated by moving the shift lever 44. The control cable 72 is slidably encased within the sleeve 68. The sleeve 68 terminates at a ferrule 70, the ferrule abutting the body 42. The control cable 72 is routed externally of the distal portion 19, between the body 42 and the medial portion 16, passing through an aperture 75 to route the cable inside the aerobar toward the handlebar 5.
The interiorly-disposed section 46 must be of sufficient length to securely grip the interior walls 50 of the aerobar 10. The longer the length of the interiorly-disposed section 46, however, the farther the shifter 40 is positioned away from the cyclist's hand, requiring the cyclist to release her grip from the upturned medial portion 16 of the aerobar 10 to effect a shift. The cyclist preferably grasps the aerobar at the upturned medial portion 16 to comfortably position her wrist while riding.
When the cyclist grips the aerobar 10 in this position to achieve these aerodynamic and ergonomic goals, her hand is placed at a far enough distance proximal to the exteriorly disposed portion 47 of the shifter 40, and more particularly, to the shift lever 44 of the shifter 40, so that the cyclist is forced to move her hands back and forth along the axis of the aerobar 10 between a gripping position and a shifting position to accomplish the shifting. This movement of the cyclist's hand releases her grip from the aerobar and may interfere with her smooth operation of the bicycle. As such, it would be preferable if one could shorten the distal portion 19 of the aerobar 10. By shortening the length of distal portion 19, one could move the shift lever 44 closer to the cyclist's hand when the cyclist's hand is in the aerobar gripping position. The cyclist would then be able to actuate the shift lever 44 without moving her hands, arms, or wrists away from the preferred ergonomic gripping position.